Fuses and earthing

• What is a common problem when dealing with electricity?

  Sudden increases in current, called surges
• What can cause surges in a circuit?

  Changes in the circuit or faults in appliances
• What are the potential dangers of electrical surges?

  Fires and electric shocks
• What safety precautions help reduce electrical risks?

  • Fuses
  • Circuit breakers
  • Earth wires
  • Double insulation
• How do fuses and circuit breakers function similarly?

  Both break the circuit during high current
• What is a fuse made of?

  A very thin piece of wire
• What happens to a fuse during a surge?

  The thin wire melts, breaking the circuit
• How are fuses typically packaged?

  In little cases with thin wire inside
• If an appliance has a normal current of 3 amps, which fuse could you use?

  A 5 amp fuse
• Why should a fuse rating be above the appliance's normal current?

  To prevent unnecessary circuit breaks
• What is a disadvantage of fuses?

  They are permanently broken after a surge
• How do circuit breakers differ from fuses?

  Circuit breakers can be reset after tripping
• What is a downside of circuit breakers?

  They are more expensive than fuses
• How can surges cause harm in appliances?

  If the live wire touches the casing
• What is the purpose of earthing in electrical appliances?

  To provide an alternative pathway for current
• How does double insulation prevent electric shocks?

  It covers the appliance in non-conductive plastic
• What type of wire does a double insulated appliance have?

  Live and neutral wires only
• What are the key features of fuses and circuit breakers?

  Fuses:

  • Simple and cheap
  • Permanently broken after a surge

  
  

  Circuit Breakers:

  • Can be reset
  • More expensive than fuses